Single-Sheet Excel Calculator

I need a straightforward Excel file made up of just one worksheet. The sheet will store raw data and rely only on basic arithmetic formulas—simple SUM, subtraction, multiplication, or average calculations—to keep totals updated automatically as I add or change numbers. No advanced functions such as VLOOKUP or SUMIF are necessary.

Please structure the layout so it is easy to follow, with clear labels and neat formatting. If practical, lock the formula cells to prevent accidental edits while leaving data-entry cells open.

Deliverable:
• A clean .xlsx file with the formulas already in place
• A brief note explaining which cells contain formulas and how to extend them if the list of entries grows

If you see any small tweaks that keep the sheet efficient without adding complexity, I’m happy to hear them.